In Poker the term Donkey or Donk has become the modern poker term for fish. A Donk is a poker player who will play with the worse cards and then somehow manage to have you beat by the the river. It's not easy to beat these kinds of players because in general they are gamblers who don't use poker skills to win, donks are willing to take a chance with any two hole cards regardless of their value or poker hand ranking. With careful observation of the play on your table you should be able to recognize these players within the first 10 hands.
Watch to see who is raising pre-flop and who calls, study their play to the showdown. If the raiser raised for no reason or the caller called with nothing you should make a note on these player, most online poker rooms allow you to write notes. You should label these types of poker players as Donks for future reference because when you got the nuts they will pay the price.
Donks also known as fish can be found playing mainly at the micro/low limit poker games in online poker rooms, they can eat away at your bankroll or double it depends on how you approach your hands. Losing with pocket aces or kings because your opponent pushes all-in pre-flop then beats you with something ridiculous like 2c3d or pocket 2's is just bad luck and you probably did the right thing calling but just accept it a gambling loss.
With high pocket pairs your odds are good pre-flop but you should always keep in mind that your opponent may have any pocket pair and flopped a set and could have you beat with three of a kind or full house. Also watch out for two cards of the same suit on the flop your opponent may have any two cards of the same suit and have you beat by the time you reach the river card. Play tight and assume they have you beat if they making bets bigger than the pot, save you stack for when you flop a set and use aggression on the donks within reasonable limits
You should add the amount you have lost to the donkey in his player notes because one day when seated at the same table he probably won't remember you but you have details and information on him. Revenge is sweet, and you already know that he is a donk so you want to get this amount back from him if not double.
The best way to beat a donk is to donk him back, it's far more rewarding when you beat him at his own game, when you finally think you have him beat on a hand make your play unpredictable by re-raising his bets and then checking like you're confused or missed the card you were hoping for, also play the hand quickly so he thinks you are making irrational decisions and will he will call your bets.
Once you have doubled your stack and taken the donks money it's probably best to leave the table while you're still up because you can be guaranteed you have got him all heated and he will want revenge.
Most online poker rooms will have donkeys playing at their micro stakes cash game tables ($0.01/$0.02) some of my personal favorite places to find fish is either most new poker rooms because their aren't many good players, 888 Poker, Full Tilt Poker, and PokerStars attract donks from around the world it's like fishing in international waters where the fish are really big.
Donks are really important to the game of poker because if everybody played poker correctly and made perfect decisions there wouldn't be much money to be made playing poker online. When losing to a donk you shouldn't never let it get you down or get heated. NEVER abuse them in the online chat it will give them satisfaction knowing they have got you mad, hoping you will make bad decisions in a poker rage in the next few hands.
Poker Donkeys can also be found playing SNG single and multi table tournaments they are either out in the first few hands or they are the chip leader who will continue to raise every hand in an attempt to steal as many blinds as they can to increase their chip stack. It's harder to beat a donk in a tournament than cash games because players have to survive in tournaments so one mistake and you could be knocked out with your top ranked hand.
Players who donk their way through a tournament generally never make it to the money anyway so if you're a tight player you can sit back and let the donks destroy each other in the early stages of a tournament. If you're willing to risk your chip stack a few all-ins or some aggressive playing with top pairs will help you double up and survive. Rebuy tournament are normally always fill of donks they can help increase the prize pools to really large amounts with the amount of rebuys being more than the entrants buy-ins.
UltimateBet Poker now known as UB have a special Seven Deuce tables where players can win a side-pot bet if they win with the hole cards seven deuce. It's not easy to win with the worst hand in poker and takes real skill to pull it off. Bluffing when playing live games works more than it does when playing poker online probably because it's more intimidating when you're face to face with your opponent as opposed to playing poker against someone online who is there to gamble and take big risks.
Phil Hellmuth has won eleven WSOP bracelets although he is considered one of the biggest fish in poker watch Phil Hellmuth VS Mike Mausow in this high stakes poker game. It's a perfect example of how a bluff can put you in a position where you have to fold your top hand where you could have won a huge pot.